Lots of people are losing it after being shocked by the unexpected death in what series creators are calling a 'fun way to shake things up.'

There was more than your average angst and outrage on Twitter last night - and it all had to do with the death of an animated dog.

Brian, a major character in FOX's long-running hit cartoon series, was killed off after being hit by a car. He was then replaced with Vinny - a tough-talking pup voiced by former Sopranos star Tony Sirico. In explaining the decision to axe Brian after 11 seasons, executive producer Steve Callaghan told E!: "This was an idea that got pitched in the writers room and it sort of caught fire, and we thought it could be a fun way to shake things up.

"As soon as this idea came up, we started talking about what the next couple episodes could be and we got very excited about the way this change will affect the family dynamics and the characters. As much as we love Brian, and as much as everyone loves their pets, we felt it would be more traumatic to lose one of the kids, rather than the family pet."

Not according to the Internet - where dogs and cats take precedence over all else. After Sunday's program aired, a campaign with the hashtag #BringBackBrian was already underway; with many, many fans voicing their outrage over the loss of the beloved canine.

While some fans are upset, others know that with "Family Guy," nothing is ultimately final when it comes to character deaths. Just a few weeks ago, Meg was even killed off but returned the next week. So it's with some certainty that Brian's death is but a short-term OMG moment.

"Our fans are smart enough and have been loyal to our show for long enough, to know that they can trust us," said Callaghan. "We always make choices that always work to the greatest benefit of the series."

Don't worry everyone: Brian will be back. Check out some of his greatest moments below.